This project will examine the normal development of the retina and its connections in the lateral geniculate nucleus of the macaque monkey and human from midfetal to adult stages. Changes in cellular morphology and the development of characteristic synaptology for each tissue will be followed by Golgi impregnation, light and electron microscopy. The morphological effects of pattern and light visual deprivation from birth on the development of monkey retina and lateral geniculate nucleus will also be studied and compared to the normal developmental sequence. This work will provide morphological information on the effects of visual deprivation on normal developmental patterns in the primate visual system. BIBLIOGRAPHIC REFERENCES: Hendrickson, A., Lund, J., and Kalina, R., The interaction of retinal lesions and eyelid closure in the monkey dorsal lateral geniculate. Presented at 5th Annual Meeting, Society for Neuroscience, New York City, Nov., 1975. Hendrickson, A., Tracing Neuronal Connections with Radioisotopes Applied Extracellularly. Fed. Proc., 34: 1612-1615, 1975.